Am 15.08.23 um 19:10 schrieb Hamza Mahfooz:

fbcon requires that we implement &drm_framebuffer_funcs.dirty. Otherwise, the framebuffer might take awhile to flush (which would manifest as noticeable lag). However, we can't enable this callback for non-fbcon cases since it might cause too many atomic commits to be made at once. So, implement amdgpu_dirtyfb() and only enable it for fbcon framebuffers on devices that support atomic KMS.

Cc: Aurabindo Pillai aurabindo.pillai@amd.com Cc: Mario Limonciello mario.limonciello@amd.com Cc: stable@vger.kernel.org # 6.1+ Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2519 Signed-off-by: Hamza Mahfooz hamza.mahfooz@amd.com

---

drivers/gpu/drm/amd/amdgpu/amdgpu_display.c | 26 ++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c index d20dd3f852fc..743db9aee68c 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c @@ -38,6 +38,8 @@ #include <linux/pci.h> #include <linux/pm_runtime.h> #include <drm/drm_crtc_helper.h> +#include <drm/drm_damage_helper.h> +#include <drm/drm_drv.h> #include <drm/drm_edid.h> #include <drm/drm_fb_helper.h> #include <drm/drm_gem_framebuffer_helper.h> @@ -532,11 +534,29 @@ bool amdgpu_display_ddc_probe(struct amdgpu_connector *amdgpu_connector, return true; } +static int amdgpu_dirtyfb(struct drm_framebuffer *fb, struct drm_file *file,

• 	  unsigned int flags, unsigned int color,
  

• 	  struct drm_clip_rect *clips, unsigned int num_clips)
  

+{

• if (strcmp(framebuffer->comm, "[fbcon]"))

• return -ENOSYS;
  

Checks like this are a pretty big NO-GO.

I'm not an expert for the display stuff, but in general this here looks like a pretty ugly hack.

Regards, Christian.

• return drm_atomic_helper_dirtyfb(framebuffer, file_priv, flags, color,

• 			 clips, num_clips);
  

+}

• static const struct drm_framebuffer_funcs amdgpu_fb_funcs = { .destroy = drm_gem_fb_destroy, .create_handle = drm_gem_fb_create_handle, };

+static const struct drm_framebuffer_funcs amdgpu_fb_funcs_atomic = {

• .destroy = drm_gem_fb_destroy,
• .create_handle = drm_gem_fb_create_handle,
• .dirty = amdgpu_dirtyfb

+};

• uint32_t amdgpu_display_supported_domains(struct amdgpu_device *adev, uint64_t bo_flags) {

@@ -1139,7 +1159,11 @@ static int amdgpu_display_gem_fb_verify_and_init(struct drm_device *dev, if (ret) goto err;

• ret = drm_framebuffer_init(dev, &rfb->base, &amdgpu_fb_funcs);

• if (drm_drv_uses_atomic_modeset(dev))

• ret = drm_framebuffer_init(dev, &rfb->base,
  

• 			   &amdgpu_fb_funcs_atomic);
  

• else

• ret = drm_framebuffer_init(dev, &rfb->base, &amdgpu_fb_funcs);
  

if (ret) goto err;